Patents by Inventor Donald W. Follstaedt

Donald W. Follstaedt has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5092392
    Abstract: An apparatus and method for monitoring and maintaining a predetermined width in the gap between a casting nozzle and a casting wheel, wherein the gap is monitored by means of at least one pneumatic gap sensor. The pneumatic gap sensor is mounted on the casting nozzle in proximity to the casting surface and is connected by means of a tube to a regulator and a transducer. The regulator provides a flow of gas through a restictor to the pneumatic gap sensor, and the transducer translates the changes in the gas pressure caused by the proximity of the casting wheel to the pneumatic gap sensor outlet into a signal intelligible to a control device. The relative positions of the casting nozzle and casting wheel can thereby be selectively adjusted to continually maintain a predetermined distance between their adjacent surfaces. The apparatus and method enables accurate monitoring of the actual casting gap in a simple and reliable manner resistant to the extreme temperatures and otherwise hostile casting environment.
    Type: Grant
    Filed: September 12, 1991
    Date of Patent: March 3, 1992
    Assignee: Armco, Inc.
    Inventors: Karl T. Bagdal, Edward L. King, Donald W. Follstaedt
  • Patent number: 5063990
    Abstract: The continuous casting of metal strip using the melt overflow process is improved by controlling the weir conditions in the nozzle to provide a more uniform flow of molten metal across the width of the nozzle and reducing the tendency for freezing of metal along the interface with refractory surfaces. A weir design having a sloped rear wall and tapered sidewalls and critical gap controls beneath the weir has resulted in the drastic reduction in edge tearing and a significant improvement in strip uniformity. The floor of the container vessel is preferably sloped and the gap between the nozzle and the rotating substrate is critically controlled. The resulting flow patterns observed with the improved casting process have reduced thermal gradients in the bath, contained surface slag and eliminated undesirable solidification near the discharge area by increasing the flow rates at those points.
    Type: Grant
    Filed: June 22, 1990
    Date of Patent: November 12, 1991
    Assignee: Armco Inc.
    Inventors: Donald W. Follstaedt, Edward L. King, Ken C. Schneider
  • Patent number: 5063988
    Abstract: Casting nozzles will provide improved flow conditions with the parameters controlled according to the present invention. The gap relationships between the nozzle slot and exit orifice must be controlled in combination with converging exit passageway to provide a smooth flow without shearing and turbulence in the stream. The nozzle lips are also rounded to improve flow and increase refractory life of the lips of the nozzle. The tundish walls are tapered to provide improve flow for supplying the melt to the nozzle. The nozzle is located about 45.degree. below top dead center for optimum conditions.
    Type: Grant
    Filed: June 22, 1990
    Date of Patent: November 12, 1991
    Assignee: Armco Inc.
    Inventors: Donald W. Follstaedt, John C. Powell, Richard C. Sussman, Robert S. Williams
  • Patent number: 5040592
    Abstract: The continuous casting of strip, ribbon and wire is improved by using a free jet nozzle which provides a fluid that follows a rotating substrate surface to the separation point. The nozzle includes an inclined surface having a ratio of its length to the gap between the substrate and the nozzle edge of 5:1 to 15:1. The inclined surface improves the ability of the jet to tangentially follow the substrate in a direction opposite to its rotation to the separation point. This also allows a close positioning of the nozzle to the substrate which serves to provide a back-up mechanical separation means by using the edge of nozzle lip. The nozzle may be rotated from its operating position for cleaning of the substrate and the nozzle.
    Type: Grant
    Filed: June 22, 1990
    Date of Patent: August 20, 1991
    Assignee: Armco Inc.
    Inventors: Edward L. King, Donald W. Follstaedt, Richard C. Sussman